My basic mentality is this:

Egwene = 3 average strength sisters (women like Eldirth or Ispan and Falion), this is supported by Aviendha's assertion of her being stronger than Amys and Melane (strong AS level women).

Nynaeve = 3 Strong Sisters (Delana, Masuri, Rafela etc)

Moiraine = 3 weak sisters (Daigian, Kumira, Siuan and Leane) which we know is true from Siuan's reduction.

IMO the books are clear that Egwene is about 80% the strength of Nynaeve and Moiraine is about 45% of Nynaeve and about 60% of Egwene.

It fits what we've seen from abilities too:

Egwene can lift about 20% less than Nynaeve can with air (while splitting her flows 4 ways)

Moiraine can lift maybe 45% less than Nynaeve's max if she used every ounce of her power.

Assuming Egwene lifted in the ball park of 375lbs in Sea Folk (3 women at about 125lbs each) while splitting her flows 4 ways and holding a a shield on a strong AS level woman in LOC and said while it wasn't easy, it wasn't all that hard either.

LOC
Summoned in Haste

Drawing a deep breath, she embraced saidar and channeled four flows before the Windfinder could react. So she knew weather, did she? Could she divide her flows four ways? Not many Aes Sedai could. One flow was Spirit, a shield she shoved onto the Windfinder to keep her from interfering. If she knew how. Each of the other three was Air, woven almost delicately around each woman, binding her arms to her sides. Lifting them was not precisely difficult, but not easy either.

Moiraine can lift 3x her body weight, maybe 350lbs using all of her strength (Siuan says that's her about her max in LOC).

LOC
To Heal Again

It was impossible. True, the simple act of picking something up was one of the hardest in channeling, but she had been able to lift nearly three times her own weight.

And Nynaeve said she could not lift both Rand and Lan at the same time in WH (Combined maybe as much as 500lbs).

WH
Blue Carp Street

"I saw them," Rand said. "They're inside now. Nynaeve, can you lift Lan and me to that rooftop from the alley behind the building?" Nynaeve frowned at Zeram's building, rubbing the belt around her waist with one hand. "One at a time, I could," she said finally. "But it would use more than half what the Well holds. I wouldn't be able to lift you down again."

and later

Something unseen wrapped snugly around Rand's chest beneath his arms, and slowly he rose into the air, floating higher until he drifted over the edge of the overhanging eave. The invisible harness vanished, and his boots dropped to the sloping roof, sliding a little on the damp gray slates. Crouching, he moved back on all fours. A few moments later, Lan floated up to land on the roof, too.

Obviously not an absolute as I don't think ability in one weave/flow can really define total strength, but it does give us some scope since all of these women are strong in Air, no Talent is involved, and it's something every channeler can do to some degree or another based on their strength.